The Turkish construction workers appeared to be the bomber's target, Somali police Col. Abdi Abdullahi said.

The military's Africa Command confirmed the deaths and said two other Americans who work for the U.S. Department of Defence were also wounded in the attack on Sunday.

The Somalia-based extremist group al-Shabab claimed responsibility for the blast in Mogadishu, saying it targeted vehicles carrying government officials.

The al-Qaida-linked al-Shabab, Africa’s deadliest Islamic extremist group, claimed responsibility for the attack and said its target had been the nearby Maka Almukarramah hotel, which is patronized by government officials.

Former Toronto security guard Mohamed Hersi was convicted in 2014 of attempting to participate in the activities of a terrorist group and providing counsel to a person to participate in terrorist activity.

Wearing a stethoscope and seated in front of a rifle and ISIS flag, he encouraged “brothers and sisters” to join the terrorist group.

The U.S. Africa Command statement says the airstrike occurred on Saturday near Jilib in Middle Juba region.

Abdihakim Guleid is one of six suspected of aiding and abetting the attack on the dusitD2 hotel complex on Tuesday that resulted in 21 people dead.

An upscale hotel complex in Kenya's capital came under attack on Tuesday, with a blast and heavy gunfire. Al-Shabab - the Somalia-based Islamic extremist group - has claimed responsibility.

The al-Qaida-linked al-Shabab extremist group, which often targets Mogadishu, claimed responsibility for the attack.